I don't think it's either viable or necessary. Gaming is enough of a secondary feature for the device that it really doesn't matter too much in the long run. It would be like counting all the generic BR/HDDVD player because some movies ship with stupid little games on them.
The iPhone is, first and foremost, a phone. NOT a gaming device. Cell phones have had games since very early on, and I don't see the iPhone as being different in that respect.
Plus, neither Apple not AT&T stores will give out sales data, and that is where all the US orders come from. Good luck estimating the market with 0% sales data... (no comment on other countries, as I don't know how they are sold anywhere but america)
Please, PLEASE do NOT feed the trolls.
fksumot tag: "Sheik had to become a man to be useful. Or less useful. Might depend if you're bi."
--Predictions--
1) WiiFit will outsell the pokemans.
Current Status: 2009.01.10 70k till PKMN Yellow (Passed: Emerald, Crystal, FR/LG)
